Concrete construction



Jan. 9, 1934. M. MORSE CONCRETE CONSTRUCTION Filed Nov. 29, 1930 IWMF. Meiuin .ZLMor-we flifiya i aiented Jan. 9, 1934 UNITED STATES PATENT OFFlCE mesne assignments,

to Edward H. Angier,

Framingham, Mass., trustee Application November 29, 1930 Serial No. 499,034

2 Claims.

This invention relates to concrete construction and a cardinal object is to provide for waterproofing such construction in an improved manner.

The invention will be well understood by reference to the following description of an illustrative embodiment thereof taken in connection with the accompanying drawing, wherein:--

Fig 1 is a perspective of a concrete floor waterproofed in accordance with my invention, with parts successively broken away;

Fig.2 is a fragmentary plan of the waterproofing membrane with parts broken away;

Fig.3 is a fragmentary section through the waterproofing membrane;

Fig. 4 is a similar section showing its action under certain conditions; and

Figs. 5 and 6 show views similar to Figs. 3 and 4 to illustrate by contrast the operation of the membrane shown.

In accordance with my invention I incorporate with a concrete slab 7 as a waterproofing membrane received between the surfaces of the slab an imperforate sheet 9 of water-resistant material which because of its form rather than because of the material of which it is composed is resiliently expansible. For this purpose I utilize paper, preferably in the nature of kraft paper, which has been craped or crinkled as by the well known roll and doctor method to render it resiliently expansible and which is rendered waterresistant by the use of a suitable water-resistant material conveniently of a bituminous nature, such, for example, as black asphalt.

In Fig. l, to simplify the figure I have shown the layer 9 as a single thickness. Preferably, however, I utilize a duplex material, as shown more particularly Figs. 2 and 3, embodying two sheets 11 and 13 of craped paper, each of which, as indicated by the stippling in Fig. 3, is impregnated throughout its body with asphalt or the like and which receive between them a layer 15 of asphalt or similar water-resisting material. I also prefer to incorporate in the layer 11 suitable material to resist any tendency of the layer 15 to become displaced between the sheets, and for this purpose it is convenient to use a coarse mesh burlap 17 embedded in the body of layer 15 and preferably applied somewhat slackly to permit it to expand with the sheets 11 and 13 independently of the natural stretchiness of the threads or yarns of which it is composed.

The sheet 9 may be mopped on to the concrete with hot asphalt in the manner in which cloth membranes have hitherto been used. On account of the slight stiffness which is found in a sheet of heavy paper, it is most easily handled and applied, while because of its resiliency it is not easily broken in handling and can be easily placed in position even on a somewhat rough surface without rupture. The concrete bonds readily to the rough surface formed by the crinkles. In use, under the shrinkage strains of the drying concrete, whether or no resulting in incipient cracks, the craped sheets expand to accommodate themselves to these strains without rupture. When they do so, the layer 15 which partakes of the wavy or crinkled character of the sheets on either side of it expands with it without break in its continuity. When, as is preferable, the sheets 11 and 13 are themselves impregnated, there is no likelihood of their soaking up some of the layer 15 to cause a thin spot. Because impregnated they are themselves of a resistant nature and will not suffer deterioration through contact with the wet concrete.

I am aware that it has hitherto been common to attempt to incorporate in a concrete slab a film of asphalt or similar water-resistant material by supporting or carrying such a film on a looosely woven web of cotton cloth. Apart from the greater convenience in applying a membrane as herein described, it will be noted that it provides unfailingly three water-resistant films, two of impregnated paper and one of asphalt between them, which will not be ruptured due to shrinkage strains. In Fig. 5 I have illustrated diagrammatically two adjacent threads 19 and 21 of a mesh of cloth receiving between them a film 23 of asphalt. Now, referring to Fig. 6, it will be seen that if shrinkage strains tend to draw the two threads 19 and 21 apart, even though the cloth itself may not break due to its natural stretch, the tendency will be to pull apart the film of asphalt which is drawn out thinner in the center and may finally break. In contrast in Fig. 4 it will be seen that the uniform layer of asphalt 15 between the two craped sheets 11 and 13 itself partakes of the nature of such a craped sheet and expands substantially uniformly.

I am aware that the invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and I therefore desire the present embodiment to be considered in all respects as illustrative and not restrictive; reference being had to the appended claims rather than to the foregoing description to indicate the scope of the invention.

I claim:

1. In combination, a slab of auto-solidified plastic and a waterproofing membrane emembedded therein comprising a pair of sheets of felted fibers formed to provide a substantial inherent structural extensibility compensating for shrinkage strains and enclosing between them a film of lentous waterproofing material.

' MELVIN L. MORSE. 

